PORTLAND, Maine — A 71-year-old Woolwich man pleaded not guilty Thursday in U.S. District Court to trafficking in poached elvers — juvenile American eels — between 2011 and 2014, according to information posted on the court’s electronic case filing system.

William Sheldon, a longtime commercial elver dealer operating as Kennebec Glass Eels, is charged with conspiracy and violating the federal Lacey Act, which prohibits interstate transport or transactions of any species of fish or wildlife illegally harvested or handled in any state.

Sheldon and another Maine man, Timothy Lewis, 46, of Phippsburg, each were indicted this month in Portland by a federal grand jury, according to a prepared statement released Thursday by the Department of Justice. Lewis also is charged with conspiracy and violating the federal Lacey Act but has not yet been arraigned, federal officials indicated.

Sheldon was released Thursday on personal recognizance bail after denying the charges. His trial date was set tentatively for May 1.

Contacted Thursday afternoon by phone, Sheldon declined to comment on his plea or the court case.

The indictments stem from a U.S. Fish and Wildlife Service investigation dubbed “Operation Broken Glass,” which has spanned across 11 states on the East Coast. Eleven people so far have pled guilty to federal charges filed in Maine, South Carolina and Virginia, and have admitted to trafficking in more than $2.75 million worth of illegally harvested elvers, according to federal prosecutors.

Among them are seven men — four of whom are Maine residents — who last October waived indictment and pleaded guilty in federal court in Portland to illegally harvesting $1.9 million worth of elvers in Virginia, New Jersey, Massachusetts and Rhode Island in 2013 and 2014. Four of the men are scheduled to be sentenced in Portland in September.

Bail conditions for Sheldon, who is considered a major player in Maine’s elver fishery, do not prevent him from fishing for or buying or selling elvers while awaiting the resolution of his case. Maine’s elver season began March 22.

Sheldon’s licenses as an elver fisherman and dealer still are active, his attorney, Walter McKee of Augusta, said Wednesday in an email.

“We will now finally have the opportunity to review all of the evidence the government says it has,” McKee said. “Where that takes us is anyone’s guess.”

The value of Maine’s elver fishery has boomed in recent years as demand in Asia for the translucent, spaghetti-like elvers has soared. Since 2012, the value of Maine’s annual total landings of elvers caught during the 10-week fishing season has averaged more than $20 million each year, with fishermen being paid on average roughly $1,600 per pound over that same time period.

According to a 2013 BuzzFeed article, which described Sheldon as an “elver kingpin,” Sheldon paid out a total of $12 million to fishermen he bought from during Maine’s 2012 elver season, when the value of the annual statewide harvest peaked at $40 million.

Sheldon did comment Thursday on the 2017 elver season so far, saying that the relatively cold weather has kept any noticeable amount of elvers from turning up along Maine’s coast, even though many fishermen have staked out their spots by erecting fyke nets along the edges of tidal waterways. He said it is not clear how high current demand in Asia might be, because Maine fishermen have not caught anything yet and don’t know what price they will be offered for their catch.

“It’s been slow,” Sheldon said. “It’s pretty hard to sell something you don’t have.”

Prosecutors alleged that from 2011 to 2014, while Sheldon was licensed in Maine and South Carolina to commercially harvest elvers, he violated the Lacey Act by buying or selling eels illegally poached in Massachusetts, North Carolina, New Jersey, Delaware, Virginia and North Carolina.

During that time, only Maine, South Carolina and Florida allowed commercial harvest of elvers, the tiny, juvenile American eels that are exported to Asia. During that time, they were selling for $1,500 per pound, the indictment said.

Investigators alleged that Sheldon conspired with at least five other people to traffic the eels and submit false documentation about the transactions.

On May 1, 2014, law enforcement agents with the U.S. Fish and Wildlife Service, the National Oceanic and Atmospheric Administration and the Maine Marine Patrol executed a search warrant at Jasper’s Motel in Ellsworth and searched two rooms rented by Sheldon.

In an affidavit filed in federal court, agents said that Sheldon encouraged fishermen, some of whom were undercover federal agents, to fish in prohibited areas and that he bought elvers that he knew had not been legally harvested.

In addition to the potential sentence, prosecutors are asking that Sheldon be required to forfeit his 2012 Ford F450 truck, which carries the Maine license plate “EELWGN.”

If convicted, Sheldon faces up to five years in prison and a $250,000 fine in addition to the truck forfeiture. He also could be prohibited from fishing for and dealing in elvers.

BDN writer Beth Brogan contributed to this report.